Micro-LED Pixel Layout for Uniform Color and Ghost-Free Displays

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Display devices using micro light emitting diodes (LEDs) face issues with asymmetrical light distribution due to crystallinity, leading to color variations when viewed from different directions and unintended parasitic capacitance causing ghost phenomena.

Innovation Solution

The display device incorporates a wiring substrate with unit pixels and electrode pads, where each light emitting diode is tilted to offset biased light distribution. Adjacent LEDs are arranged symmetrically with respect to the tilt angle, and the distance between electrode pads varies to compensate for the tilt, ensuring uniform light distribution and reducing parasitic capacitance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If light emitting diodes are grown on sapphire substrate with tilted crystal surface, then manufacturing process is simplified, but asymmetrical light distribution occurs causing color variation with viewing direction

Engineering Contradiction:
Improveease of manufactureVSAvoidcolor uniformity
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent applies asymmetry by intentionally tilting adjacent light emitting diodes in opposite directions. Instead of making all LEDs identical and symmetric, the invention creates a controlled asymmetric arrangement where alternating LEDs have opposite tilt angles, which compensates for the asymmetric light distribution and achieves uniform color appearance from different viewing angles.

Inventive Principle:
Principle #4Asymmetry

2Device complexity

If light emitting diodes are arranged in general configuration, then device complexity is reduced, but parasitic capacitance occurs causing ghost phenomenon

Engineering Contradiction:
Improvedevice complexityVSAvoiddisplay quality
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent uses asymmetry in electrode pad arrangement to reduce parasitic capacitance. By making the distances between adjacent electrode pads different (first distance and second distance), the invention breaks the symmetry of electric field distribution, which reduces unintended parasitic capacitance and prevents ghost phenomena while maintaining a relatively simple device structure.

Inventive Principle:
Principle #4Asymmetry

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This solution effectively offsets biased light distribution, improves color viewing angle by correcting color differences, and reduces parasitic capacitance, thereby eliminating ghost phenomena and ensuring uniform brightness across the display.

Implementation Method 1

a light emitting diode (LED), as a well-known semiconductor light emitting device that converts current into light

Methodology Applied
Scientific EffectLight emitting diode: Light Emitting Diode

Data Source

PatentEP4503126A1Display device using semiconductor light emitting diodes
Publication Date: 2025.02.05 LG ELECTRONICS INC
  • EP4503126A1 patent drawingFigure 1~2
  • EP4503126A1 patent drawingFigure 3~4(b)
  • EP4503126A1 patent drawingFigure 5~6(B)

AI summary

A display device is applicable to a display-related technical field, and a display device using micro light emitting diodes (LED) are disclosed. The display device using light emitting diodes includes a wiring substrate in which a plurality of unit pixels is defined, at least one electrode pad disposed in each of the unit pixels to define a plurality of unit sub-pixels, and at least one light emitting diode configured to have a tilt angle at which a side surface of the light emitting diode is inclined to one side, and a bonding surface electrically connected to the electrode pad. Two light emitting diodes adjacent to each other are arranged symmetrically with respect to the tilt angle, and a distance between two electrode pads adjacent to each other varies depending on positions of the electrode pads..